Build error when using WITH_GCRYPT=ON

[Vic Lee <llyzs@xxxxxxx>]

Hi,

I have both openssl and gcrypt and I want to compile libssh with gcrypt,
so I add this option.

$ cmake -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_BUILD_TYPE=Debug
-DWITH_GCRYPT=ON ..

When I "make" a lot of compilation error pop up from file dh.c. I found
out that in config.h, both HAVE_LIBCRYPTO and HAVE_LIBGCRYPT were
defined to 1. I manually comment "#define HAVE_LIBCRYPTO 1" and it built
fine.

I am not familiar with cmake system, please help to check how to fix it?

Thanks,

Vic